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Ang II regulates RhoGDI1 stability and cell proliferation via SUMOylation. However, how Ang II regulates RhoGDI1 SUMOylation remains unknown. In this study, we focused on revealing the effects of E1 subunits (Aos1 and Uba2) on RhoGDI1 SUMOylation in HA-VSMC proliferation.The expressions of Aos1, Uba2, and SUMO1 were suppressed by siRNA transfection. HA-VSMCs were treated with Ang II (100 nM) for 24 h. RhoGDI1 SUMOylation and ubiquitination were checked by co-immunoprecipitation. Cell proliferation was detected by EdU assay.Uba2 or Aos1 suppression significantly inhibited Ang II-induced SUMO2/3 modification of RhoGDI1 and cell proliferation, while not affecting SUMO1 modification of RhoGDI1. In addition, Uba2 or Aos1 suppression promoted RhoGDI1 ubiquitination and degradation. These indicate that both Uba2 and Aos1 are necessary for SUMO2/3 modification of RhoGDI1 that participates in cell proliferation by regulating RhoGDI1 ubiquitination and stability. Moreover, SUMO1 suppression did not affect RhoGDI1 ubiquitination and degradation and cell proliferation in Ang II-induced VSMCs, suggesting that SUMO1 modification does not participate in RhoGDI1 stability and cell proliferation.This study reveals the differences between SUMO2/3 and SUMO1 modification in regulating RhoGDI1 stability and Ang II-mediated cell proliferation. Schematic summary of roles of SUMO1 and SUMO2/3 modification of RhoGDI1 in regulating RhoGDI1 stability and cell proliferation in Ang II-treated HA-VSMCs.

This work presents an improved approach to consider the effect of any intermediate piles between the two piles in pile groups. Based on the thin ring shear model of concentric cylinder and elastic theory, a multi-pile analysis model under axial load is proposed with full consideration of the mutual reinforcing effect between super-long piles. A theoretical derivation of interaction coefficient and the deformation of super-long pile groups which simultaneously consider the reinforcing effect and the existence of other piles in pile groups was carried out. Example analysis shows that the analytical solution agrees well with the experimental results. In this work, the error between the calculated result of the presented model and the measured value is 25% less than that in the traditional model. The multi-pile model fully analyzes the interaction mode between multiple piles and considers the mutual reinforcing effect among the piles, which makes up for the deficiency in traditional settlement calculation of pile groups. Consequently, the model proposed can accurately reflect the working characteristics of super-long pile groups in actual engineering.

Al-polymer laminated membranes are widely used in large aerospace structures. When the laminated membranes are pressurized, wrinkles emerge, which have an important effect on the performance of the structures during operation. This paper describes the numerical simulation and experimental investigation of wrinkles in laminated membranes. The nonlinear postbuckling analysis method, based on laminated thin-shell elements, was used to simulate the onset, growth, and final configuration of wrinkles when laminated membranes are subjected to external loads. The simulations are conducted with the ANSYS finite element package. Changing regularities of number, wavelength, and range for the wrinkles during the onset and growth processes are investigated. The wrinkles of laminated membranes with different design parameters such as material selection, ply number, ply angle, and ply mode are predicted. Devices that can be used to clamp and load laminated membranes in several load cases were designed and developed. A 3D photogrammetry system was constructed to characterize wrinkling patterns of laminated membranes subjected to shear displacement loads. By comparing the results of numerical analysis and experimental results, the accuracy of the numerical analysis method was verified. This study work is expected to inform wrinkling simulation and shape control of aerospace laminated membrane structures.

According to the vibration characteristics of the round window, a mechanical model of a round window membrane is established. The Euler equation of the round window and the complementary boundary conditions are derived by the variational principle. Combined with the Bessel function, an analytical solution of the round window displacement is obtained by MATHEMATICA. Combined with clinical characteristics of round window membrane lesion, the effect of sound transmission due to thickening of the round window membrane caused by the otitis media, shrinkage of the round window membrane area caused by otosclerosis, and hardening of the round window membrane itself is analyzed. The results show that with thickening of the round window membrane, the displacement of the round window membrane is decreased. In the meantime, with hardening of the round window membrane and shrinkage of the membrane area, the maximum displacement of the round window membrane is gradually reduced, leading to a decrease in sound transmission. Thus, the analytical analysis can avoid interference of environment and the technical level of personnel, and it can evaluate transmission performance of the round window membrane efficiently, providing a theoretical basis for the reverse excitation of artificial prosthesis.

Structural design of nuclear power plant project is an important sub-discipline of civil engineering. Especially after appearance of the fourth generation advanced high temperature gas cooled reactor, structural mechanics in reactor technology becomes a popular subject in structural engineering. As basic ingredients of reflector in reactor, graphite bricks are subjected to high temperature and irradiation and the stress field of graphite structures determines integrity of reflector and makes a great difference to safety of whole structure. In this paper, based on assumptions of elasticity, side reflector is regarded approximately as a straight cylinder structure and primary creep strain is ignored. An analytical study on stress of IG110 graphite parts is present. Meanwhile, a finite element procedure for calculating stresses in the IG110 graphite structure exposed in the high temperature and irradiation is developed. Subsequently, numerical solution of stress in IG110 graphite structure is obtained. Analytical solution agrees well with numerical solution, which indicates that analytical derivation is accurate. Finally, influence of temperature, irradiation dimensional change, creep and Poisson’s ration on stress field, variation of stress against time and deformation of structure are discussed.

The folding patterns and deployment dynamic characteristics of conical inflatable capsule structures were investigated. A six-fold-line method of packing a conical shell surface was designed. The fold-line layouts and relation formulas of the fold angles were determined. The folded state of the inflatable capsule structure was parametrically modeled; then, the deployment dynamic analysis model was established using ANSYS/LS-DYNA software. The dynamic characteristics of the inflatable capsule structure in orbit were numerically simulated. Thus, the deployment configurations and the time history curves of the dynamic characteristics were obtained. The results verified the feasibility of the fold pattern and the deployment dynamic analysis model. The influences of the residual gases from the packing process on the subsequent deployment process were investigated. The results indicated that a small amount of residual gas can lead to structures that cannot deploy smoothly, and two methods were presented to avoid this challenge. These works provide technical support for the structural designs of this type of inflatable capsule structure.

Space-deployable habitat modules provide artificial habitable environments for astronauts and will be widely used for the construction of future space stations and lunar habitats. A novel structural design concept of space-deployable habitat modules consisting of flexible composite shells and deployable trusses has been proposed. Geometric relationships of deployable trusses based on two types of scissor elements were formulated. Flexible composite shells of space habitat modules were designed, and a nonlinear FEA model using ANSYS software was described. Considering folding efficiencies, stiffness, and strength of the structures, the influences of design parameters were analyzed and the final design scheme of space-deployable habitat modules was determined. After detailing the structural designs, low-speed impact dynamic responses between the structures and a stainless steel cylinder were simulated. The analysis results show that dynamic responses are only significant at the point of low-speed impact. The works will provide technical supports for structural designs and engineering applications of space-deployable habitat modules.

Many novel materials exhibit a property of different elastic moduli in tension and compression. One such material is graphene, a wonder material, which has the highest strength yet measured. Investigations on buckling problems for structures with different moduli are scarce. To address this new problem, firstly, the nondimensional expression of the relation between offset of neutral axis and deflection curve is derived based on the phased integration method, and then using the energy method, load-deflection relation of the rod is determined; Secondly, based on the improved constitutive model for different moduli, large deformation finite element formulations are developed and combined with the arc-length method, finite element iterative program for rods with different moduli is established to obtain buckling critical loads; Thirdly, material mechanical properties tests of graphite, which is the raw material of graphene, are performed to measure the tensile and compressive elastic moduli, moreover, buckling tests are also conducted to investigate the buckling behavior of this kind of graphite rod. By comparing the calculation results of the energy method and finite element method with those of laboratory tests, the analytical model and finite element numerical model are demonstrated to be accurate and reliable. The results show that it may lead to unsafe results if the classic theory was still adopted to determine the buckling loads of those rods composed of a material having different moduli. The proposed models could provide a novel approach for further investigation of non-linear mechanical behavior for other structures with different moduli.

2,3,4',5-tetrahydroxystilbene 2-O-β-D-glucoside (TSG), a resveratrol analog with glucoside, is purified from a traditional Chinese herbal medicine polygonum multiflorum. It has been extensively studied in last decade and known to exert strong anti-inflammatory, anti-oxidative, anti-apoptotic, and free radical scavenging activities, and therefore has been listed as a potential agent for disease therapies. Recent studies extend well-beyond effects of TSG on the injury of neurons, cardiomyocytes and endothelial cells, and report important functions of TSG in a lot of pathophysiological conditions. For example, TSG has been shown to prevent the production of pro-inflammatory cytokines in microglia and macrophages in vitro, and ameliorate pro-inflammatory responses in animal models with neurodegeneration, atherosclerosis, and rat paw or ear oedema. TSG can prevent the proliferation of vascular smooth cells, gastrointestinal dysfunctions, platelet aggregation, osteoblastic injury, diabetic nephropathy and melanogenesis. TSG is also indicated to facilitate long-term potentiation and learning and memory in both normal and pathological conditions. These effects to some extent enrich the understanding about the role of TSG in disease prevention and therapy. However, to date, we still have no outlined knowledges about the pharmacological effects of TSG, though the role of TSG in aging and Alzheimer's disease has been reviewed in recent years. Here, we summarize the current pharmacological developments of TSG as well as its possible mechanisms in disease prevention and therapy, aiming to push the understanding about the protective role of TSG as well as its preclinical assessment of novel applications.

Purpose – The purpose of this paper is to solve temperature stress for bending beam with different moduli under different constraints subject to nonlinear temperature. Design/methodology/approach – The equations of neutral axis position, normal stress, and displacement of bending beam with different moduli subjected to nonlinear temperature were derived based on different moduli elasticity theory. Meanwhile, iterative procedure was programmed to solve the nonlinear equations. The analytical solution can return back into the result of the same modulus theory, and the analytical solution was compared with finite element numerical solution. It shows that the analytical model proposed in this paper is reliable to use. Furthermore, the influence of different moduli characteristics on the temperature stress and deformation is discussed. Findings – The mechanical behavior of the bending beam with different moduli subject to nonlinear temperature is quite different from the one that is subjected to force. The bending beam maybe exist two neutral axis, and the reasonable selection of tension modulus and compression modulus can improve the distribution of the normal stress and reduce the maximum tensile stress or the maximum compressive stress. Originality/value – The crack produced by temperature stress will affect the integrity and the durability of the structure. The solution for temperature problem with different moduli theory is rarely reported at home and board. In view of this, this paper will do some exploratory research-temperature stress for bending beam with different moduli.

Many civil-engineering materials and novel materials developed in recent years exhibit a property of different elastic moduli in tension and compression. One such material is graphene, a wonder material, which has the highest strength yet measured. However, the dominant failure of structures composed of this high-strength material is often attributed to buckling problems. Investigations on buckling problems for structures with different moduli are scarce. To address this new problem, the present paper develops a semianalytical method for the critical buckling loads of variable–cross section slender rods with different moduli. Based on the variational principle, a differential equation of the deflection of these structures is derived for the first time. By developing a nonlinear iterative program and using the variational iteration method, the critical buckling loads are obtained. Then, buckling tests and numerical simulation were conducted for slender rods made from graphite with different moduli....

Two calculation models are established for inner soil pressure of opened bottom elliptical barrel structure (OBEBS) using penetration of negative pressure method. One model is for construction stage, pressure of inner soil in cabins at this stage was divided into three zones: active zone, transition zone and passive zone. The other model is for operational stage, pressure of inner soil in cabins at this stage was divided into two zones: active zone and passive zone. The theoretical analytical solutions of inner soil pressure for construction stage and operational stage were derived. The analytical formulas derived in this paper and finite element method were used to analyze the inner soil pressure of OBEBS at same time and condition. The models were used to calculate the carrying capacity of the former site and settlement of the structure. The models of inner soil pressure provided a scientific method for design and construction of the new multi-position structure.

In this study, we focused mainly on establishing a new sensitive method to identify location of damages in Service Bridge. The improved method of combination of Autoregressive models (AR) and autoregressive models with exogenous inputs (ARX) was applied to identify the damage in Service Bridge. Firstly, an improved AR-ARX model was established for damage identification of bridge on service. Secondly, the detailed steps of identifying location of damages are explained using proposed damage diagnosis method. Finally,the improved AR-ARX model was used to identify location of damage in a two-span steel beam. The results of calculated showed the damage diagnosis method based on improved AR-ARX model that considered the ambient excitation is much more powerful and accurate than AR-ARX method. So the proposed method can apply to bridge damage detection with few acceleration sensors. This study laid the foundation for the bridge identification.

Based on structure principle of shear connector, a new type of perfobond hoop has been proposed. The mechanical advantage of PBH has been compared to traditional shear connector by mechanical analysis. According to the measurement and reinforcement requirement suggested by ECSS, the finite element model has been established. The important design parameters which have influence on carrying capacity of PBH shear connector have been analyzed, such as concrete strength, hole numbers, bore diameter, bar diameter and the thickness of steel plate with hole. Carrying capacity calculation expression of PBH shear connector was put forward by regression analysis. The calculation expression has been verified by four groups of shear resistance experiments and the test results agree well with the calculated value by the expression.

In this study, we want to find out the relationship between the bridge natural frequency and the bridge foundation scour depth. The Improved Ibrahim Time Domain (IITD) method and the finite element models are applied to solve the problem. Firstly, IITD method was described in detail for using to solve the natural frequency at ambient excitation. Secondly, the detailed steps of expiring the relationship between bridge natural frequencies and foundation scour depth are explained using IITD method and finite element techniques. Finally, the natural frequency of Qujiang Bridge is calculated at different scour depth. The detailed analysis of the natural frequency of the bridge with the variation of scour depth can able to explore the impact of bridge scour damage for structural safe operation. The results of calculated showed the IITD method that considered the ambient excitation is much more powerful and accurate than Irahim Time Domain (ITD) method. So IITD can apply to bridge scour damage detection with finite element techniques. This study laid the foundation for the bridge scour identification.

The embedded large-diameter cylinder had been widely used in coastal engineering since it could be embedded into ground directly without excavation. A 3D elastic-plastic finite element model has been established to analyze the distribution and development of the friction resistance on large-diameter cylinder under the wave load. The results show that the development of friction on different areas of the cylinder is unsynchronized. The friction resistance first developed on the outer surface of the structure, after that, the inner friction began to develop. Only in certain areas the firction resistance can achieve ultimate value at the ultimate state.

The mechanical models of Perfobond Hoop (PBH) and Perfobond Leiste (PBL) shear connector were compared, based on their structure traits. PBH shear connector is more reasonable than PBL shear connector in mechanic. Then, the carrying capacities of the two forms of shear connectors were compared. It shows by the experimental result that PBH shear connector is superior to PBL shear connector in carrying capacity. The model of the experiment specimen were established using finite element method, then, the FEM model was verified by comparing it with the experiment results. Furthermore, the factors which may have influence on carrying capacity of PBH shear connector were

This paper presents the study of negative skin friction of the superlong pile caused by the soil settlement under large-scale surcharge loading. Based on the displacement equilibrium principle and transfer matrix method, with the introduction of a load transfer model considering shaft resistance softening, the analytical model of negative skin friction of superlong pile under surcharge loading is established by considering the three-dimensional consolidation settlement along the pile under surcharge loading, the compression deformation of pile, and the soil settlement around pile-end. Three-dimensional Biot consolidation is used to derive the settlement of soil surrounding pile and the settlement formula is simplified by using the Laplace and Hankel integral transform. Furthermore, the analysis is conducted for an engineering example using the theoretical model and FEM simulation method. The results are also compared with the corresponding measured data. The characteristics of negative skin friction of superlong pile under surcharge loading are obtained, and the effect of soil parameters on negative skin friction is discussed as well, which can offer valuable reference for the design of superlong piles.

Many engineering materials exhibit different elastic properties under the extension and compression. Among these materials, the concrete is a typical material which has different extension modulus and compression modulus. Based on different modulus theory, mechanical analysis was performed in this paper for reinforced concrete beams, stress formula was deduced, and the corresponding formula was applied to concrete structures with second-class crack control, which has improved the original crack control conditions in the code for design of concrete structures in China based on the classical modulus theory.

Many novel materials, developed in recent years, have obvious properties with different modulus of elasticity in tension and compression. The ratio of their tensile modulus to compressive modulus is as high as five times. Nowadays, it has become a new trend to study the mechanical properties of these bimodular materials. At the present stage, there are extensive studies related to the strength analysis of bimodular structures, but the investigation of the buckling stability problem of bimodular rods seems to cover new ground. In this article, a semi-analytical method is proposed to acquire the buckling critical load of bimodular slender rod. By introducing non-dimensional parameters, the position of neutral axis of the bimodular rod in the critical state can be determined. Then by combining the phased integration method, the deflection differential equation of bimodular pin-ended slender rod is deduced. In addition, the buckling critical load is obtained by solving this equation. An example, which is conducted by comparing the calculation results between the three of the methods including the laboratory tests, numerical simulation method and the method we developed here, shows that the method proposed in the present work is reliable to use. Furthermore, the influence of bimodular characteristics on the stability is discussed and analyzed.

The calculation and analysis of single pile settlement was one of the important geotechnical engineering issues, and many geotechnical engineers and scholars investigated and formed a systematic analysis method. Among the existing methods of analysis methods, the elasticity theory method was relatively mature. However, the traditional elasticity theory method could not consider the slip properties between pile and soil, and did not match the actual working properties of pile foundation. In this paper, based on Mindlin's solution, the pile is assumed to be elastic and the relationship between shear stress and relative displacement at the pile-soil interface is assumed to follow hyperbolic function, then series equations were derived and solved by Finite Difference Method. Two cases were demonstrated and the computed results agreed very well with testing data. The advantage of the analysis method proposed was that the interaction of pile and pile, and pile and soil can be considered.

In order to research on the stress change and influencing factor of whole construction process of simply supported to Continuous system T-beam bridge, combined with Guizhou Bai-long bridge, the stress change is carried out the real time inspection in each construction stage, and the finite element model is established to analyse Stress changes in whole construction process. The monitoring value is ​​more consistent with the theoretical value in each stage , monitoring dates and theoretical calculations showed that pre-stressed is the main factor of stress changes in construction process.Pre-stressed tension in negative moment region has obvious influence on the stress of middle span, the stress of top and bottom plates in wet joints will be equivalent after tendons tension in negative moment Region.

Taking Tianjin Yonghe bridge for example, the finite element method is adopted to simulate each stages of cable replacement process, the dates of tension, the alignment of main beam and the change of stress before and after cable replacement are compared and analysed, The measured value is greatly consistent with calculated value, Stress state of the bridge has been greatly improved, the weight of main beam bearing by the cable will be shared by a few closed cable after unloading, so the cables which are more serious corroded should be replaced.

Currently, super-long piles are designed based on the theory of normal long piles. There is no recognized reasonable mechanical model for qualitative analysis. In this paper, based on load transfer function method, an improved load transfer model is proposed, which gives consideration to both the degradation of skin friction and the asynchronous work between lateral friction resistance and pile-tip resistance caused by pile-soil slip. By applying it in various working conditions, the corresponding pile-soil displacement and axial force of super-long piles are derived. Finally, the proposed model is validated by comparing its analytical solutions to the results of FEM and practical survey of super-long piles, and it provides a new efficient approach for the study of the mechanical behavior of super-long single pile.

Based on the bearing capacity behavior and load transfer mechanism of super-long pile in soft soil, the three-stage hyperbolic softening model is presented as the load transfer function of pile-side soil, and tri-linear model is introduced to simulate the characteristics of sediments in pile end. The differential equations are established by dealing with the states of static equilibrium, with considering the character of layered stratum and pile-soil interaction. The analytical solutions on different states are obtained by power series. Based on transfer matrix method, soil mechanics and elastic theory, a set of analytical equations and calculating method for the axial load-settlement curve of pile top in layered ground are established. Lastly, the calculating parameters are obtained by theoretically approaching to actually measure load-settlement curve in soft soil area. The calculating contrast to adjacent test pile is carried out by the method and the results are satisfactory.

In this paper, a three-stage softening load transfer model, based on existing experimental data of super-long piles, is proposed; the hyperbola load transfer model is adopted to simulate the nonlinear deformation of pile-tip soil; and the elastic-plastic model of concrete is introduced, giving consideration to the super-long pile shaft deformation under heavy axial loads. Then the models above are implemented into pile-soil load transfer differential equation, and after being solved by iteration method, the nonlinear method for load transfer model of super-long pile in layered soil is established. After that programming of the model calculation is worked out. By comparison with engineering instance, it is shown that the method proposed in this paper is convenient and reliable in engineering practice.

In this paper, based on pile-soil interaction, the calculating method for the negative skin friction of pile in layered soil is proposed. Two load conditions, axial load on the top and overloading on soil around pile are presented, respectively. The transfer matrix method is used to analyze the first condition, while the soil consolidation theory and finite difference method are used to investigate the second condition numerically. The results can offer valuable references for both theoretical research and engineering design of long pile bearing larger negative skin friction.

In this paper, a nonlinear three-dimensional finite element model for super-long pile and soil interaction is established. In this model, contact elements are applied to simulate the nonlinear behavior of interaction of super-long pile and soil. A nonlinear elastic constitutive model for concrete is employed to analyze stress-strain relation of pile shaft under the axial load and the Duncan-Chang’s nonlinear constitutive model is used to reflect nonlinear and inelastic properties of soil. The side friction resistance, axial force, pile-tip resistance, and developing trend of soil plastic deformation are obtained and compared with measured results from static load tests. It is demonstrated that a super-long pile has the properties of degradation of side friction resistance and asynchronous action between side and pile-tip resistance, which is different from piles with a short to medium length.

Materials with different modulus in tension and compression have a wide application in engineering practice, especially the composite materials developed in recent years, which have properties of different tension-compression modulus. To exploring the general features of mechanical properties of structures with different modulus, the dimensionless equation of finite element was deduced for structure with different modulus, and corresponding finite element program was developed .the stresses of the cantilever beam by program of the theory with different modulus. The impacts on member stresses resulted from the change of structure size, external load and the ratio of different modulus are compared and analyzed. Finally, we have drawn a conclusion that the property of different modulus of the material is very important to its stress, and have given out suggestions on the optimization of state of structural stress.

A new damage identification method for bridge scour was proposed, in the case that it was difficult to detect bridge scour depth applying testing equipment. Through integrative application of the eigensystem realization algorithm (ERA) and method of support vector machine (SVM), this method was used to identify the scour depths of bridge under conditions of ambient excitation. The following three steps are necessary for the application of this method to identify bridge scour. Firstly, a sample library about scour depth and upper structure vibration response was established using numerical methods and support vector machine method. Secondly, free response signal of bridge were extracted from random vibration signal of bridge upper structure using random decrement technique. Thirdly, based on above two steps, the bridge scour depth was identified using ERA and SVM. In the process of applying the method to identify bridge scour depth, the key is to find the sensitive points for scour depth of substructure using sample library and to gather the vibration response signal of accelerated velocity under conditions of ambient excitation. It was identified that the method has higher recognition accuracy and better robustness through experiments on a real bridge. The method provided a new way for identifying scour depth of bridges.

It is shown that many materials in practical engineering have different moduli in tension and compression. Especially, graphene, a magical material with the highest strength, is a kind of bi-modulus material. In this paper, mechanical response of bi-modulus Winkler foundation beam under nonlinear temperature distribution along height of the beam is studied. A new and convenient method, “intersecting line criterion”, is proposed to certify number of neutral axis in foundation beam and governing equation (set) of position of neutral axis is established, which is solved by iteration procedure of Newton’s method in Matlab. Semi-analytical solutions of stress, deflection and bending moment are subsequently obtained. Meanwhile, a finite element calculation procedure for calculating the temperature stress in bi-modulus structures is developed. Return the analytical solution to the result of the same modulus theory, and compare the analytical solution with finite element procedure solution and common finite element software Abaqus simulation solution. It shows that both of semi-analytical solution and calculation procedure proposed are reliable to use. Finally, discrepancies between nonlinear temperature effect and linear temperature and external force effect are discussed, which may supply some suggestions for calculation and optimization of such structures and members.

A method of damage identification of piles was established by using vibration characteristics. The approach focused on the application of the element strain energy and sensitive modals. A damage identification equation of piles was deduced using the structural vibration equation. The equation contained three major factors: change rate of element modal strain energy, damage factor of pile, and sensitivity factor of modal damage. The sensitive modals of damage identification were selected by using sensitivity factor of modal damage firstly. Subsequently, the indexes for early-warning of pile damage were established by applying the change rate of strain energy. Then the technology of computational analysis of wavelet transform was used to damage identification for pile. The identification of small damage of pile was completely achieved, including the location of damage and the extent of damage. In the process of identifying the extent of damage of pile, the equation of damage identification was used in many times. Finally, a stadium project was used as an example to demonstrate the effectiveness of the proposed method of damage identification for piles. The correctness and practicability of the proposed method were verified by comparing the results of damage identification with that of low strain test. The research provided a new way for damage identification of piles.

Nonlinear numerical model of Large Diameter Cylindrical Structure and Soil Interaction is constructed. The Dynamic Response of Large Diameter Cylindrical Structure under measured seismic wave is studied. The following conclusions can be obtained: the displacement change of cylinder at the free end is the biggest, the stress of cylinder at the bottom is the biggest and has large circumferential moment, the There is a rotating point between the structural midpoint and the bottom, the structure and the soil inside cylinder rotates around the rotating point. There is a certain lag in the displacement curve compared to the curve of seismic wave acceleration, the peak time-point of speed response curve is slightly earlier than that of displacement response curve, but the shape of the two curves is similar. Results can provide evidence for the design of deeply embedded large diameter cylinder.

We present a novel fiber optic flow sensor system by using two fiber Bragg gratings (FBGs) and a cantilever beam structure in this paper. This fiber optic flow sensor uses two FBGs that are bonded on both sides of a cantilever beam to measure the flow rate by monitoring the FBG wavelength changes caused by the bending of the cantilever beam. Cross sensitivity of the temperature dependence of the sensor can be compensated automatically. We fabricate the FBG flow sensor and test it in the laboratory-scaled flow set-up. The testing results demonstrate its high resolution and repeatability for the fluid flow rate measurements. Based on the analysis of test results, the fiber optic flow system will be optimized in the materials of the cantilever beam and the process of sensor fabrication, so as to finally be used in the oil field.

Non-equilibrium interferometric Fiber Bragg Grating (FBG) sensor is suitable for the accurate measurements of high-frequency dynamic stress, vibration, etc because of its high sensitivity and high frequency response compared to other types of FBG sensors. In this paper, a Phase Generation Carrier (PGC) demodulation technique of non-equilibrium interferometric FBG sensor that based on ARCTAN algorithm by using an arctangent algorithm with a simple method, has been investigated, which can avoid the high-frequency noise increases, the error accumulation, the integrator signal jump of the integrator and other inherent weaknesses in the system. ARCTAN has a better response characteristic of the mutant signals, especially for low-frequency large-signal that can be demodulated with a greater range. The experimental result demonstrate that implementing measured resolution can up to 10ne/√Hz@500Hz in vibration strain, a signal sampling rate to 100 KHz and a frequency response range up to 1 KHz. This method can improve the performance of the system greatly which has potential significance for practical sensor application.

As an important member of optical fiber sensor, fiber optic Extrinsic Fabry-Perot Interferometric (EFPI) sensor has prospects for a wide range of industrial applications due to its small size, compact configuration, good reliability and flexibility. In a white light based fiber optic EFPI sensor system, which has the advantages of large dynamic range and high resolution, spectral analysis equipment is the most important part which takes the major cost of the system. Therefore, multiplexing spectral analysis equipment to measure multiple sensors simultaneously is an effective and necessary way that can save the cost of the whole sensor system. In this paper, a scheme based on the frequency division multiplexing of EFPI optical fiber sensors is proposed. Two EFPI sensors with different gap lengths are parallely connected through the optical fiber coupler. The overlapped interference spectrum of the two EFPI sensors is measured by using an optical spectrum analyzer, which is separated into two individual interference spectrums with a Finite Impuse Response (FIR) band-pass filter. Their envelope components are extracted with Hilbert transform, and then the interference spectrums are normalized by the envelope components. The respective gap lengths of the two EFPI sensors are achieved with the cross correlation calculation. Using this frequency division spectral analysis method, a two-channel multiplexing EFPI sensor system is implemented in the laboratory. The deployment of this frequency division multiplexing technology can greatly reduce the cost of the whole system which has extensive potential applications for distributed fiber optic EFPI sensor system.

Surface Plasmon Resonance (SPR) has been widely investigated for chemical and biological sensing applications. Especially, fiber optic SPR sensors have recently drawn considerable attention because of their fundamentally simpler structure, lower cost, and suitability for remote-sensing applications. This paper will present a research work for a novel multichannel SPR sensing technology. Based on the Kretschmann's SPR theory, we theoretically investigate the surface parameters effects to SPR wavelength changes. Emphasis will be placed on a theoretical design and numerical simulation of a multichannel fiber optic SPR sensing scheme based on a geometrical tapered fiber optic sensor probe that coated with nanoparticles imprinted polymer on the SPR sensing region. The parameter effects of SPR sensing area that include metal thickness, sensing area length and dielectric overcoat layer. SPR spectra that change with incidence angle and wavelength are investigated by using numerical calculations and simulations. While nanoparticles imprinted polymer for enhancement of sensitivity can serve as an enhanced transduction mechanism for recognition and sensing of target analytes in accordance with different requirements, the scheme of a multichannel fiber optic SPR sensor can be further adapted to the design and development of multi-channel optical fibers SPR sensor probes by combining SPR with other technology as a comprehensive sensor design.

In this paper, based on load transfer method, a deformation calculating method for uplift piles was presented, in which the nonlinear relation between the reaction force and the displacement of tension piles was simulated by the generalized load transfer model. The displacement on top of the uplift pile was adjusted by dichotomy, and at lower load levels, the deformation of uplift piles could be predicted satisfactorily. In order to facilitate analysis in engineering, a detailed analysis schedule for deformation of uplift piles were given. The analysis method for uplift piles established can be applied for the cases not only to calculate the settlement and bearing capacity of uplift piles, but also to analyze the load transfer law of uplift piles in layered ground. Comparisons between the calculated results showed good agreement with experimental data.

Comparing to core-modes of optical fibers, some cladding-modes are more sensitive to the surroundings which are very valuable to sensing application; recently, a novel type of FBG sensor with core-offset structure attracts more and more interests. Normally, the forward core-mode is not only reflected and coupled to the backward core mode by the Fiber Bragg Grating in the step-type photosensitive single mode fiber, but also coupled to the backward cladding-modes and the radiation modes, eventually they will leak or be absorbed by the high refraction index coating layer. These backward cladding-modes can also be used for sensing analysis. In this paper, we propose and develop a core-offset structure to obtain the backward core-mode and backward cladding-modes by using the wavelength shift of the backward core-mode and the power of the backward cladding-modes in Fiber Bragg Grating sensor, and the power of the backward cladding-modes are independent from temperature variation. We develop a mode coupling sensor model between the forward core-mode and the backward cladding-modes, and demonstrate two coupling methods in the core-offset structure experimentally. The sensor is fabricated and demonstrated for refractive index monitoring. Some specific works are under investigation now, more analysis and fabrication will be done to improve this cladding-mode based sensor design for applicable sensing technology.

Optical sensors based on nanoparticles induced Localized Surface Plasmon Resonance are more sensitive to real-time chemical and biological sensing, which have attracted intensive attentions in many fields. In this paper, we establish a simulation model based on nanoparticles imprinted polymer to increase sensitivity of the LSPR sensor by detecting the changes of Surface Plasmon Resonance signals. Theoretical analysis and numerical simulation of parameters effects to absorption peak and light field distribution are highlighted. Two-dimensional simulated color maps show that LSPR lead to centralization of the light energy around the gold nanoparticles, Transverse Magnetic wave and total reflection become the important factors to enhance the light field in our simulated structure. Fast Fourier Transfer analysis shows that the absorption peak of the surface plasmon resonance signal resulted from gold nanoparticles is sharper while its wavelength is bigger by comparing with silver nanoparticles; a double chain structure make the amplitude of the signals smaller, and make absorption wavelength longer; the absorption peak of enhancement resulted from nanopore arrays has smaller wavelength and weaker amplitude in contrast with nanoparticles. These simulation results of the Localized Surface Plasmon Resonance can be used as an enhanced transduction mechanism for enhancement of sensitivity in recognition and sensing of target analytes in accordance with different requirements.

This paper proposed a new feature extraction method for lip-reading, named DCT+LSDA. Discrete Cosine Transform (DCT) is a popular method used to reduce the dimension of the data and it has been very efficient in lipreading. Linear Discriminant Analysis (LDA) is a method to study the class relationship between data points, it is very useful method for dimensionality reduction and feature extraction. For lipreading system, the change of the lip is a non-rigid deformation, only considering the discrimination of different class is not enough, the local structure information is important too. So in this paper, the Locality Sensitive Discriminate analysis (LSDA) is used, it is a method considers both the Discriminant and geometrical structure of the data. The experimental results show that the proposed method DCT+LSDA is performed better than DCT+PCA and DCT+LDA, and it also shows that the endpoint detection is crucial for the lipreading system.

Tympanosclerosis is a typical middle ear disease, which is one of the main causes of conduction deafness. We investigate the effects of tympanosclerosis and lesion excision on sound transmission of the human ear by using finite element technique. Based on CT scan images from Zhongshan Hospital of Fudan University on the normal human middle ear, numerical values of the CT scans were obtained by further processing of the images using a self-compiled program. The CT data of the right ear from a healthy volunteer were digitalized and imported into PATRAN software to reconstruct the finite element model of the ear by a self-compiling program. A frequency response analysis was made for the model, and comparative analysis was made between the calculated results and experimental data, which validated the model in this paper. The results show that the sclerosis of the ligaments and tensor muscle in the middle ear caused by force on the ossicles is larger than the normal ear and the amplitude of the stapes footplate is larger than the normal ear. This leads to a decrease of the final conductive hearing function. Furthermore, the excision of the stapes ligament and tensor tympani is good for the restoration of normal hearing. This paper provides new research perspective for clinical treatment.